diff --git a/PREUPLOAD.cfg b/PREUPLOAD.cfg
index 125b469..7b533a4 100644
--- a/PREUPLOAD.cfg
+++ b/PREUPLOAD.cfg
@@ -1,3 +1,2 @@
 [Hook Scripts]
-versioner = tools/versioner/preupload.sh
 notice = tools/update_notice.sh
diff --git a/libc/Android.bp b/libc/Android.bp
index 5d0e8c7..9bba776 100644
--- a/libc/Android.bp
+++ b/libc/Android.bp
@@ -2036,15 +2036,12 @@
     defaults: ["crt_defaults"],
 }
 
-// The following module lives in prebuilts/ndk because we need to preprocess the
-// headers to include ifdef guards for __ANDROID_API__. Update with
-// bionic/tools/update_headers.sh.
-// ndk_headers {
-//     name: "common_libc",
-//     from: "include",
-//     to: "",
-//     srcs: ["include/**/*.h"],
-// }
+preprocessed_ndk_headers {
+    name: "common_libc",
+    from: "include",
+    to: "",
+    license: "NOTICE",
+}
 
 ndk_headers {
     name: "libc_uapi",
diff --git a/libc/bionic/libc_init_common.cpp b/libc/bionic/libc_init_common.cpp
index e5654c3..9094fc5 100644
--- a/libc/bionic/libc_init_common.cpp
+++ b/libc/bionic/libc_init_common.cpp
@@ -62,7 +62,11 @@
 char** environ;
 
 #if defined(__i386__)
-__LIBC_HIDDEN__ void* __libc_sysinfo = nullptr;
+__attribute__((__naked__)) static void __libc_int0x80() {
+  __asm__ volatile("int $0x80; ret");
+}
+
+__LIBC_HIDDEN__ void* __libc_sysinfo = reinterpret_cast<void*>(__libc_int0x80);
 
 __LIBC_HIDDEN__ void __libc_init_sysinfo(KernelArgumentBlock& args) {
   __libc_sysinfo = reinterpret_cast<void*>(args.getauxval(AT_SYSINFO));
diff --git a/libc/versioner-dependencies/arm/arch-arm b/libc/versioner-dependencies/arm/arch-arm
new file mode 120000
index 0000000..cc94225
--- /dev/null
+++ b/libc/versioner-dependencies/arm/arch-arm
@@ -0,0 +1 @@
+../../arch-arm/include/
\ No newline at end of file
diff --git a/libc/versioner-dependencies/arm/kernel_uapi_asm-arm b/libc/versioner-dependencies/arm/kernel_uapi_asm-arm
new file mode 120000
index 0000000..3c7584d
--- /dev/null
+++ b/libc/versioner-dependencies/arm/kernel_uapi_asm-arm
@@ -0,0 +1 @@
+../../kernel/uapi/asm-arm
\ No newline at end of file
diff --git a/libc/versioner-dependencies/arm64/arch-arm64 b/libc/versioner-dependencies/arm64/arch-arm64
new file mode 120000
index 0000000..2d9128a
--- /dev/null
+++ b/libc/versioner-dependencies/arm64/arch-arm64
@@ -0,0 +1 @@
+../../arch-arm64/include/
\ No newline at end of file
diff --git a/libc/versioner-dependencies/arm64/kernel_uapi_asm-arm64 b/libc/versioner-dependencies/arm64/kernel_uapi_asm-arm64
new file mode 120000
index 0000000..7ee6fd2
--- /dev/null
+++ b/libc/versioner-dependencies/arm64/kernel_uapi_asm-arm64
@@ -0,0 +1 @@
+../../kernel/uapi/asm-arm64
\ No newline at end of file
diff --git a/libc/versioner-dependencies/common/clang-builtins b/libc/versioner-dependencies/common/clang-builtins
new file mode 120000
index 0000000..7bd481c
--- /dev/null
+++ b/libc/versioner-dependencies/common/clang-builtins
@@ -0,0 +1 @@
+../../../../external/clang/lib/Headers/
\ No newline at end of file
diff --git a/libc/versioner-dependencies/common/kernel_android_uapi b/libc/versioner-dependencies/common/kernel_android_uapi
new file mode 120000
index 0000000..fd78315
--- /dev/null
+++ b/libc/versioner-dependencies/common/kernel_android_uapi
@@ -0,0 +1 @@
+../../kernel/android/uapi/
\ No newline at end of file
diff --git a/libc/versioner-dependencies/common/kernel_uapi b/libc/versioner-dependencies/common/kernel_uapi
new file mode 120000
index 0000000..d5cb8ee
--- /dev/null
+++ b/libc/versioner-dependencies/common/kernel_uapi
@@ -0,0 +1 @@
+../../kernel/uapi/
\ No newline at end of file
diff --git a/libc/versioner-dependencies/mips/arch-mips b/libc/versioner-dependencies/mips/arch-mips
new file mode 120000
index 0000000..56ed021
--- /dev/null
+++ b/libc/versioner-dependencies/mips/arch-mips
@@ -0,0 +1 @@
+../../arch-mips/include/
\ No newline at end of file
diff --git a/libc/versioner-dependencies/mips/kernel_uapi_asm-mips b/libc/versioner-dependencies/mips/kernel_uapi_asm-mips
new file mode 120000
index 0000000..94bb3db
--- /dev/null
+++ b/libc/versioner-dependencies/mips/kernel_uapi_asm-mips
@@ -0,0 +1 @@
+../../kernel/uapi/asm-mips
\ No newline at end of file
diff --git a/libc/versioner-dependencies/mips64/arch-mips64 b/libc/versioner-dependencies/mips64/arch-mips64
new file mode 120000
index 0000000..4893b57
--- /dev/null
+++ b/libc/versioner-dependencies/mips64/arch-mips64
@@ -0,0 +1 @@
+../../arch-mips64/include/
\ No newline at end of file
diff --git a/libc/versioner-dependencies/mips64/kernel_uapi_asm-mips b/libc/versioner-dependencies/mips64/kernel_uapi_asm-mips
new file mode 120000
index 0000000..94bb3db
--- /dev/null
+++ b/libc/versioner-dependencies/mips64/kernel_uapi_asm-mips
@@ -0,0 +1 @@
+../../kernel/uapi/asm-mips
\ No newline at end of file
diff --git a/libc/versioner-dependencies/x86/arch-x86 b/libc/versioner-dependencies/x86/arch-x86
new file mode 120000
index 0000000..6426384
--- /dev/null
+++ b/libc/versioner-dependencies/x86/arch-x86
@@ -0,0 +1 @@
+../../arch-x86/include/
\ No newline at end of file
diff --git a/libc/versioner-dependencies/x86/kernel_uapi_asm-x86 b/libc/versioner-dependencies/x86/kernel_uapi_asm-x86
new file mode 120000
index 0000000..1b7a73d
--- /dev/null
+++ b/libc/versioner-dependencies/x86/kernel_uapi_asm-x86
@@ -0,0 +1 @@
+../../kernel/uapi/asm-x86/
\ No newline at end of file
diff --git a/libc/versioner-dependencies/x86_64/arch-x86_64 b/libc/versioner-dependencies/x86_64/arch-x86_64
new file mode 120000
index 0000000..684d74e
--- /dev/null
+++ b/libc/versioner-dependencies/x86_64/arch-x86_64
@@ -0,0 +1 @@
+../../arch-x86_64/include/
\ No newline at end of file
diff --git a/libc/versioner-dependencies/x86_64/kernel_uapi_asm-x86 b/libc/versioner-dependencies/x86_64/kernel_uapi_asm-x86
new file mode 120000
index 0000000..1b7a73d
--- /dev/null
+++ b/libc/versioner-dependencies/x86_64/kernel_uapi_asm-x86
@@ -0,0 +1 @@
+../../kernel/uapi/asm-x86/
\ No newline at end of file
diff --git a/tests/dl_test.cpp b/tests/dl_test.cpp
index ee9b2e1..aa8bd57 100644
--- a/tests/dl_test.cpp
+++ b/tests/dl_test.cpp
@@ -24,6 +24,7 @@
 
 #include <string>
 
+#include "gtest_globals.h"
 #include "utils.h"
 
 extern "C" int main_global_default_serial() {
@@ -86,4 +87,26 @@
 #endif
 }
 
+TEST(dl, preinit_system_calls) {
+#if defined(__BIONIC__)
+  std::string helper = get_testlib_root() +
+      "/preinit_syscall_test_helper/preinit_syscall_test_helper";
+  chmod(helper.c_str(), 0755); // TODO: "x" lost in CTS, b/34945607
+  ExecTestHelper eth;
+  eth.SetArgs({ helper.c_str(), nullptr });
+  eth.Run([&]() { execve(helper.c_str(), eth.GetArgs(), eth.GetEnv()); }, 0, nullptr);
+#endif
+}
+
+TEST(dl, xfail_preinit_getauxval) {
+#if defined(__BIONIC__)
+  std::string helper = get_testlib_root() +
+      "/preinit_getauxval_test_helper/preinit_getauxval_test_helper";
+  chmod(helper.c_str(), 0755); // TODO: "x" lost in CTS, b/34945607
+  ExecTestHelper eth;
+  eth.SetArgs({ helper.c_str(), nullptr });
+  eth.Run([&]() { execve(helper.c_str(), eth.GetArgs(), eth.GetEnv()); }, 0, nullptr);
+#endif
+}
+
 // TODO: Add tests for LD_PRELOADs
diff --git a/tests/libs/Android.bp b/tests/libs/Android.bp
index 5eb16c5..a031fe9 100644
--- a/tests/libs/Android.bp
+++ b/tests/libs/Android.bp
@@ -547,3 +547,17 @@
     shared_libs: ["libcfi-test"],
     ldflags: ["-Wl,--rpath,${ORIGIN}/.."],
 }
+
+cc_test {
+    name: "preinit_getauxval_test_helper",
+    host_supported: false,
+    defaults: ["bionic_testlib_defaults"],
+    srcs: ["preinit_getauxval_test_helper.cpp"],
+}
+
+cc_test {
+    name: "preinit_syscall_test_helper",
+    host_supported: false,
+    defaults: ["bionic_testlib_defaults"],
+    srcs: ["preinit_syscall_test_helper.cpp"],
+}
diff --git a/tests/libs/libs_utils.h b/tests/libs/libs_utils.h
index f11cbe7..7dae241 100644
--- a/tests/libs/libs_utils.h
+++ b/tests/libs/libs_utils.h
@@ -17,13 +17,11 @@
 #ifndef LIBS_UTILS_H
 #define LIBS_UTILS_H
 
+#include <assert.h>
 #include <stdio.h>
 #include <stdlib.h>
 
-#define CHECK(x)                                                            \
-  do {                                                                      \
-    fprintf(stderr, "CHECK(" #x ") failed at %s:%d\n", __FILE__, __LINE__); \
-    if (!(x)) abort();                                                      \
-  } while (0)
+#define CHECK(e) \
+    ((e) ? static_cast<void>(0) : __assert2(__FILE__, __LINE__, __PRETTY_FUNCTION__, #e))
 
 #endif  // LIBS_UTILS_H
diff --git a/tests/libs/preinit_getauxval_test_helper.cpp b/tests/libs/preinit_getauxval_test_helper.cpp
new file mode 100644
index 0000000..2a79b97
--- /dev/null
+++ b/tests/libs/preinit_getauxval_test_helper.cpp
@@ -0,0 +1,39 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <errno.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/auxv.h>
+
+#include "libs_utils.h"
+
+static unsigned long g_AT_RANDOM;
+static unsigned long g_AT_PAGESZ;
+
+static void preinit_ctor() {
+  g_AT_RANDOM = getauxval(AT_RANDOM);
+  g_AT_PAGESZ = getauxval(AT_PAGESZ);
+}
+
+__attribute__((section(".preinit_array"), used)) void (*preinit_ctor_p)(void) = preinit_ctor;
+
+int main() {
+  // Did getauxval during preinit get the same results as getauxval now?
+  CHECK(getauxval(AT_RANDOM) == g_AT_RANDOM);
+  CHECK(getauxval(AT_PAGESZ) == g_AT_PAGESZ);
+  return 0;
+}
diff --git a/tests/libs/preinit_syscall_test_helper.cpp b/tests/libs/preinit_syscall_test_helper.cpp
new file mode 100644
index 0000000..9b6b6df
--- /dev/null
+++ b/tests/libs/preinit_syscall_test_helper.cpp
@@ -0,0 +1,40 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <errno.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/auxv.h>
+
+#include "libs_utils.h"
+
+static ssize_t g_result;
+static int g_errno;
+
+static void preinit_ctor() {
+  // Can we make a system call?
+  g_result = write(-1, "", 1);
+  g_errno = errno;
+}
+
+__attribute__((section(".preinit_array"), used)) void (*preinit_ctor_p)(void) = preinit_ctor;
+
+int main() {
+  // Did we get the expected failure?
+  CHECK(g_result == -1);
+  CHECK(g_errno == EBADF);
+  return 0;
+}
diff --git a/tools/update_headers.sh b/tools/update_headers.sh
deleted file mode 100755
index 0095d50..0000000
--- a/tools/update_headers.sh
+++ /dev/null
@@ -1,53 +0,0 @@
-#!/bin/bash
-DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
-cd $DIR
-
-which versioner >/dev/null 2>&1
-if [ $? -ne 0 ]; then
-  >&2 echo "versioner not in path; run mma in $DIR/versioner"
-  exit 1
-fi
-
-VERSION=$(git rev-parse --short HEAD)
-git diff-index --quiet HEAD
-DIRTY=$?
-git branch -r --contains HEAD | grep -q aosp/master
-SUBMITTED=$?
-
-if [ $DIRTY -ne 0 ]; then
-  >&2 echo "Warning: bionic has uncommitted changes"
-  VERSION="${VERSION}-dirty"
-elif [ $SUBMITTED -ne 0 ]; then
-  >&2 echo "Warning: current HEAD does not exist in aosp/master"
-  VERSION="${VERSION}-unsubmitted"
-fi
-
-PREBUILTS_DIR=$ANDROID_BUILD_TOP/prebuilts/ndk
-BRANCH_NAME=$(git -C $PREBUILTS_DIR symbolic-ref --short -q HEAD)
-if [ $? -ne 0 ]; then
-  BRANCH_NAME=update-bionic-headers-$VERSION
-  echo "prebuilts/ndk has detached head; creating branch $BRANCH_NAME"
-  repo start $BRANCH_NAME $PREBUILTS_DIR
-else
-  echo "prebuilts/ndk already on branch $BRANCH_NAME"
-fi
-
-HEADERS_INSTALL=$PREBUILTS_DIR/headers
-if [ -d "$HEADERS_INSTALL" ]; then
-  git -C $PREBUILTS_DIR rm -r --ignore-unmatch $HEADERS_INSTALL
-  if [ -d $HEADERS_INSTALL ]; then
-    rm -r $HEADERS_INSTALL
-  fi
-fi
-
-versioner -p versioner/platforms versioner/current versioner/dependencies \
-  -o $HEADERS_INSTALL
-if [ $? -ne 0 ]; then
-  >&2 echo "Header preprocessing failed"
-  exit 1
-fi
-
-cp ../libc/NOTICE $PREBUILTS_DIR
-
-git -C $PREBUILTS_DIR add $HEADERS_INSTALL $PREBUILTS_DIR/NOTICE
-git -C $PREBUILTS_DIR commit -m "Update bionic headers to $VERSION."
diff --git a/tools/versioner/dependencies/arm/arch-arm b/tools/versioner/dependencies/arm/arch-arm
deleted file mode 120000
index ed69f41..0000000
--- a/tools/versioner/dependencies/arm/arch-arm
+++ /dev/null
@@ -1 +0,0 @@
-../../../../libc/arch-arm/include
\ No newline at end of file
diff --git a/tools/versioner/dependencies/arm/kernel_uapi_asm-arm b/tools/versioner/dependencies/arm/kernel_uapi_asm-arm
deleted file mode 120000
index fabed85..0000000
--- a/tools/versioner/dependencies/arm/kernel_uapi_asm-arm
+++ /dev/null
@@ -1 +0,0 @@
-../../../../libc/kernel/uapi/asm-arm
\ No newline at end of file
diff --git a/tools/versioner/dependencies/arm64/arch-arm64 b/tools/versioner/dependencies/arm64/arch-arm64
deleted file mode 120000
index 21a21d4..0000000
--- a/tools/versioner/dependencies/arm64/arch-arm64
+++ /dev/null
@@ -1 +0,0 @@
-../../../../libc/arch-arm64/include
\ No newline at end of file
diff --git a/tools/versioner/dependencies/arm64/kernel_uapi_asm-arm64 b/tools/versioner/dependencies/arm64/kernel_uapi_asm-arm64
deleted file mode 120000
index 16e74a3..0000000
--- a/tools/versioner/dependencies/arm64/kernel_uapi_asm-arm64
+++ /dev/null
@@ -1 +0,0 @@
-../../../../libc/kernel/uapi/asm-arm64
\ No newline at end of file
diff --git a/tools/versioner/dependencies/common/clang-builtins b/tools/versioner/dependencies/common/clang-builtins
deleted file mode 120000
index fc27e65..0000000
--- a/tools/versioner/dependencies/common/clang-builtins
+++ /dev/null
@@ -1 +0,0 @@
-../../../../../external/clang/lib/Headers
\ No newline at end of file
diff --git a/tools/versioner/dependencies/common/kernel_android_uapi b/tools/versioner/dependencies/common/kernel_android_uapi
deleted file mode 120000
index bcf6daa..0000000
--- a/tools/versioner/dependencies/common/kernel_android_uapi
+++ /dev/null
@@ -1 +0,0 @@
-../../../../libc/kernel/android/uapi
\ No newline at end of file
diff --git a/tools/versioner/dependencies/common/kernel_uapi b/tools/versioner/dependencies/common/kernel_uapi
deleted file mode 120000
index 2a915ef..0000000
--- a/tools/versioner/dependencies/common/kernel_uapi
+++ /dev/null
@@ -1 +0,0 @@
-../../../../libc/kernel/uapi
\ No newline at end of file
diff --git a/tools/versioner/dependencies/mips/arch-mips b/tools/versioner/dependencies/mips/arch-mips
deleted file mode 120000
index 7f2f104..0000000
--- a/tools/versioner/dependencies/mips/arch-mips
+++ /dev/null
@@ -1 +0,0 @@
-../../../../libc/arch-mips/include
\ No newline at end of file
diff --git a/tools/versioner/dependencies/mips/kernel_uapi_asm-mips b/tools/versioner/dependencies/mips/kernel_uapi_asm-mips
deleted file mode 120000
index dcd1955..0000000
--- a/tools/versioner/dependencies/mips/kernel_uapi_asm-mips
+++ /dev/null
@@ -1 +0,0 @@
-../../../../libc/kernel/uapi/asm-mips
\ No newline at end of file
diff --git a/tools/versioner/dependencies/mips64/arch-mips64 b/tools/versioner/dependencies/mips64/arch-mips64
deleted file mode 120000
index 48cea72..0000000
--- a/tools/versioner/dependencies/mips64/arch-mips64
+++ /dev/null
@@ -1 +0,0 @@
-../../../../libc/arch-mips64/include
\ No newline at end of file
diff --git a/tools/versioner/dependencies/mips64/kernel_uapi_asm-mips b/tools/versioner/dependencies/mips64/kernel_uapi_asm-mips
deleted file mode 120000
index dcd1955..0000000
--- a/tools/versioner/dependencies/mips64/kernel_uapi_asm-mips
+++ /dev/null
@@ -1 +0,0 @@
-../../../../libc/kernel/uapi/asm-mips
\ No newline at end of file
diff --git a/tools/versioner/dependencies/x86/arch-x86 b/tools/versioner/dependencies/x86/arch-x86
deleted file mode 120000
index d0f016a..0000000
--- a/tools/versioner/dependencies/x86/arch-x86
+++ /dev/null
@@ -1 +0,0 @@
-../../../../libc/arch-x86/include
\ No newline at end of file
diff --git a/tools/versioner/dependencies/x86/kernel_uapi_asm-x86 b/tools/versioner/dependencies/x86/kernel_uapi_asm-x86
deleted file mode 120000
index 0efae62..0000000
--- a/tools/versioner/dependencies/x86/kernel_uapi_asm-x86
+++ /dev/null
@@ -1 +0,0 @@
-../../../../libc/kernel/uapi/asm-x86
\ No newline at end of file
diff --git a/tools/versioner/dependencies/x86_64/arch-x86_64 b/tools/versioner/dependencies/x86_64/arch-x86_64
deleted file mode 120000
index deb647d..0000000
--- a/tools/versioner/dependencies/x86_64/arch-x86_64
+++ /dev/null
@@ -1 +0,0 @@
-../../../../libc/arch-x86_64/include
\ No newline at end of file
diff --git a/tools/versioner/dependencies/x86_64/kernel_uapi_asm-x86 b/tools/versioner/dependencies/x86_64/kernel_uapi_asm-x86
deleted file mode 120000
index 0efae62..0000000
--- a/tools/versioner/dependencies/x86_64/kernel_uapi_asm-x86
+++ /dev/null
@@ -1 +0,0 @@
-../../../../libc/kernel/uapi/asm-x86
\ No newline at end of file
diff --git a/tools/versioner/preupload.sh b/tools/versioner/preupload.sh
deleted file mode 100755
index 45d6cca..0000000
--- a/tools/versioner/preupload.sh
+++ /dev/null
@@ -1,9 +0,0 @@
-#!/bin/bash
-
-if ! which versioner > /dev/null; then
-  echo "versioner not found (lunch and mma in bionic)"
-  exit 1
-fi
-
-versioner -r arm -r arm64
-exit $?
diff --git a/tools/versioner/src/Android.bp b/tools/versioner/src/Android.bp
index d1362d0..c5afa56 100644
--- a/tools/versioner/src/Android.bp
+++ b/tools/versioner/src/Android.bp
@@ -41,18 +41,8 @@
                 "-fno-rtti",
             ],
         },
-        darwin: {
-            enabled: false,
-        },
         windows: {
             enabled: false,
         },
     },
-
-    product_variables: {
-        unbundled_build: {
-            // Only do this when Clang is available.
-            enabled: false,
-        },
-    },
 }